A vehicle seat can include an adjustable headrest mounted to a backrest of the vehicle seat. The headrest can be moved in a generally vertical direction relative to the seat. Two posts are mounted to the headrest. Two guide sleeves are located within the backrest of the vehicle seat, and a bushing is received in each of the two guide sleeves. Each post is receivable in one of the two guide sleeves.
Each post includes a plurality of notches. One bushing includes a mechanism that is received in one of the notches, securing the post and the attached headrest in a position. When the headrest is to be moved to another position relative to the backrest of the vehicle seat, the mechanism of the bushing is removed from the notch of the post, allowing the post, and therefore the attached headrest, to slide in the generally vertical direction relative to the backrest of the vehicle seat to a desired position. Once the headrest is in the desired position, the mechanism is released to allow the mechanism to engage another notch of the post, securing the headrest in the desired position.